1. Field of the Invention
The present invention relates to a plant containing vitamin B12 and a method of producing a plant containing vitamin B12.
2. Description of the Related Art
Vitamin B12 is an essential vitamin required for maintaining human health. Vitamin B12 is required in as small an amount as 2.4 μg per adult per day whereas most of the other essential vitamins and minerals are required in an amount of several mg or more per day. It is known that the deficiency of vitamin B12 causes diseases including malignant anemia. Recently, further study is underway on vitamin B12 and the responsibility of vitamin B12 for causing arteriosclerosis, Alzheimer's disease, and delayed sleep syndrome has been elucidated.
At present, it is known that the most important role of vitamin B12 in humans is to participate in the C1 metabolism of a vitamin B12-dependent methionine synthase system. Vitamins other than vitamin B12, such as folic acid and vitamin B6 are also involved in the C1 metabolism. These vitamins play a role in functioning cells normally by methylating principally amino acids (e.g. homocysteine), nucleic acids, and physiologically active substances. When the normal metabolism is impaired, disorders such as megaloblastic anemia, arteriosclerosis, and neuropathy may be induced.
Vitamin B12 is water soluble and relatively tolerable to heat, so that it will not be vaporized or destroyed so much during cooking. When vitamin B12 is taken as food into a human body, it is modified with an intrinsic factor of glycoprotein secreted into gastric juice and the vitamin B12 bound to the intrinsic factor is absorbed through the small intestine. Because of this, persons whose stomach has been surgically removed suffer from a disease caused by a deficiency of vitamin B12, in some cases. Vitamin B12 is therefore parenterally administrated to the person after surgery.
On the other hand, since the ability of people to absorb vitamin B12 decreases with age, old people are chronically deficient in vitamin B12. Also, a vitamin B12 deficiency sometimes appears in enthusiastic vegetarians. In this case, oral administration of vitamin B12 effectively works.
Vitamin B12 is produced only by limited types of vitamin B12-producing bacteria. Since animals usually take bacteriologically produced vitamin B12, a large amount of vitamin B12 is contained in the body. Naturally, animal food such as liver, egg, and seafood becomes to contain a large amount of vitamin B12. In contrast, the content of vitamin B12 in vegetable food is negligibly small except for seaweeds. Since vitamin B12-producing bacteria may be attached to seaweeds such as laver, it is conceivable that vitamin B12 is contained in seaweeds.
To maintain health, people usually take vegetable rich in vitamin and mineral, including beans and fruits, in various forms. To prevent unbalanced nutrition caused by busy life of people in the modern society, a wide variety of multivitamin pills and drinks are marketed as supplemental agents for supplying essential nutrients. However, it is preferable that various kinds of nutrients are taken simultaneously in the form of natural food. It follows that food enriched with vitamins and minerals has been demanded.
Vegetables basically contain rich vitamin and mineral. Since vegetables can supply various types of vitamins together, they are considered as excellent natural food. The Ministry of Health, Labor and Welfare recommends, in the promotion movement titled “Healthy Japan 21”, that not less than 350 g of vegetable food and not less than 120 g of dark green and dark yellow vegetable/day per adult should be taken. However, even if a large amount of vegetable is daily taken, vitamin B12 is still insufficient since general vegetables rarely contain vitamin B12.
Therefore, it is desired that not only healthy people but also people described below take a health-food plant containing a sufficient amount of vitamin B12 
(1) People not fond of animal food
(2) People allergic to animal food
(3) Busy people who do not have time to take well-balanced food
(4) old people whose teeth are too weak to take meat daily
(5) Vegetarians
(6) People who have a stomach problem due to ulcer
(7) People who are not willing to take vitamin in the form of pills.
It is considered that these people are always short of vitamin B12 and sometimes lacking in vitamin B12. Since vitamin B12 is indispensable for maintaining human health, it is significantly important to provide vitamin B12 in easy-to-take form.
Prior Art
To make up for the shortage of vitamin, there is an idea that a plant enriched with vitamins and minerals is grown and processed into health food. More specifically, such an idea has been directed to water-soluble vitamins and minerals originally contained in a plant. However, vitamin B12 is not originally contained in a plant but biologically synthesized by bacteria. Furthermore, no one has considered that vitamin B12 is taken from cultivated plant itself. For this reason, people not fond of animal food take vitamin B12 as a medicine by taking a multivitamin pill.
Taking vitamin supplement is one of the means for preventing vitamin deficiency. However, there are some people who does not like taking pills. In view of taking well-balanced nutrition, it is desirable to take vitamin B12 from a natural source such as a cultivated plant. Unfortunately, a plant containing a sufficient amount of vitamin B12 has not yet been cultivated up to present.
In the case of a large-size vegetable, which takes a long time to grow up, vitamin B12 may be sprayed directly to a plant or injected into the soil in order to introduce vitamin B12 to the plant. However, since vitamin B12 is used in a diluted form in these methods, the content per unit weight will not be improved. In addition, since vitamin B12 is expensive, it is desirable that vitamin B12 will be introduced into a plant by an inexpensive method consuming a small amount of vitamin B12.
In these circumstances, it seems to be really useful to develop a novel means which allows to take vitamin B12 (2.4 μg/day per adult) easily at least from a plant through daily meals by introducing a large amount of vitamin B12 into a plant originally containing no vitamin B12.
Conventional methods of introducing vitamin B12 into a plant are described in the following publications.
1. Jpn. Pat. Appln. KOKOKU Publication No. 61-56209
This invention is directed to a plant growth-controlling agent containing vitamin B12 as an active ingredient. The publication describes that the active ingredient, vitamin B12, has an extremely distinguishable plant growth-controlling activity, which includes a fruit-bearing promoting activity, fruit-drop preventing activity, fruit-growth promoting activity, and an activity of preventing production of rusty fruits. If vitamin B12 is applied to fruits such as citrus fruits (e.g. oranges) and grapes, and fruit vegetables such as berries, eggplants, and cucumbers, the period until harvest can be significantly reduced and the yield (number of fruits) and the quality of the fruits can be improved. The present invention is similar to the invention of this document in that vitamin B12 is used but differs in method, time, and purpose of using vitamin B12.
2. Jpn. Pat. Appln. KOKOKU Publication No. 60-36402
This invention relates to a method of reducing an acid component, more specifically, a method of reducing acid, thereby increasing sugar of a fruit. In other words, the present invention is directed to reducing a sour taste by administering a solution containing B-series vitamins to fruit trees or fruit vegetable. In the method, a single vitamin B or a mixture of at least two vitamins of the B series is dissolved in a small amount of water or solvent, and then the resultant solution is either sprayed onto the surfaces of leaves of a fruit tree or a fruit vegetable or injected into the soil. In this way, a sour taste can be reduced and thereby a sweet taste increases. The present invention is similar to the invention disclosed in the document in that vitamin B12 is used but differs in method, time and purpose of using vitamin B12.
3. Jpn. Pat. Appln. KOKAI Publication No. 03-5409
The invention relates to an agent for accelerating the differentiation of a flower bud by use of the interaction between cytokinin, gibberellin, nucleic acid, and at least one of vitamins. The differentiation of a flower bud is accelerated by spraying vitamin B12 and thereby shortening the period up to the harvest.
The present invention is similar to the invention disclosed in the document in that vitamin B12 is used but differs in method, time and purpose of using vitamin B12.